In the prior art, video cassette recording and playback machines are well known and some such machines include mechanisms enabling one to tune various desired stations through the use of an included knob in conjunction with setting of an automatic recording mechanism incorporated in the device so that one may record various programs automatically. While some more sophisticated such machines include programming devices which utilize a remote control and a display selectively displayed on the associated television monitor, most such programming devices incorporate a plurality of small tuning wheels contained within a compartment accessible through an openable closure on the device housing.
These tuning wheels are extremely small and only protrude from a surface of the housing of the device a small amount so that when it is desired to rotate one or more tuning wheels in preprogramming the device, it is sometimes difficult to frictionally engage the small surface area which is exposed on each tuning wheel. Thus a need has developed for a device which may be added to an existing video cassette recording and playback machine to facilitate the easy turning of the tuning wheels where desired.
The following patents are known to applicant: U.S. Pat. Nos. 186,304 to Brauer, 451,987 to Underwood, 1,399,329 to Vandercook, 2,613,540 to Keim, 3,089,088 to Roberts, et al., 3,285,078 to Siebold and 3,447,386 to Berenbaum, et al.
Each of the above listed United States patents teaches the concept of a drive mechanism including friction gearing. However, none of these devices discloses the concept of an add-on device designed to be installed on an existing video cassette recording and playback machine for the purpose of facilitating the easy turning of a pre-existing tuning wheel contained in the housing thereof. As such, the above listed references are believed to be of only general interest concerning the teachings of the present invention.